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					<h1>CodeIgniter User Guide Version 2.0.3</h1>
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		<h1>Field Data</h1>


		<h2>$this->db->list_fields()</h2>
		<p>Returns an array containing the field names. This query can be
			called two ways:</p>


		<p>
			1. You can supply the table name and call it from the
			<dfn>$this->db-></dfn>
			object:
		</p>

		<code>
			$fields = $this->db->list_fields('table_name');<br /> <br />

			foreach ($fields as $field)<br /> {<br /> &nbsp;&nbsp;&nbsp;echo
			$field;<br /> }
		</code>

		<p>2. You can gather the field names associated with any query you
			run by calling the function from your query result object:</p>

		<code>
			$query = $this->db->query('SELECT * FROM some_table'); <br /> <br />

			foreach ($query->list_fields() as $field)<br /> {<br />
			&nbsp;&nbsp;&nbsp;echo $field;<br /> }
		</code>


		<h2>$this->db->field_exists()</h2>

		<p>Sometimes it's helpful to know whether a particular field
			exists before performing an action. Returns a boolean TRUE/FALSE.
			Usage example:</p>

		<code>
			if ($this->db->field_exists('field_name', 'table_name'))<br /> {<br />
			&nbsp;&nbsp; // some code...<br /> }
		</code>

		<p>
			Note: Replace <em>field_name</em> with the name of the column you are
			looking for, and replace <em>table_name</em> with the name of the
			table you are looking for.
		</p>


		<h2>$this->db->field_data()</h2>
		<p>Returns an array of objects containing field information.</p>
		<p>Sometimes it's helpful to gather the field names or other
			metadata, like the column type, max length, etc.</p>


		<p class="important">Note: Not all databases provide meta-data.</p>

		<p>Usage example:</p>

		<code>
			$fields = $this->db->field_data('table_name');<br /> <br /> foreach
			($fields as $field)<br /> {<br /> &nbsp;&nbsp;&nbsp;echo
			$field->name;<br /> &nbsp;&nbsp;&nbsp;echo $field->type;<br />
			&nbsp;&nbsp;&nbsp;echo $field->max_length;<br />
			&nbsp;&nbsp;&nbsp;echo $field->primary_key;<br /> }
		</code>

		<p>If you have run a query already you can use the result object
			instead of supplying the table name:</p>

		<code>
			$query = $this->db->query("YOUR QUERY");<br /> $fields =
			$query->field_data();
		</code>


		<p>The following data is available from this function if supported
			by your database:</p>

		<ul>
			<li>name - column name</li>
			<li>max_length - maximum length of the column</li>
			<li>primary_key - 1 if the column is a primary key</li>
			<li>type - the type of the column</li>
		</ul>


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